Answer:
- <u>The arrow labeled 4: from gas to liquid.</u>
Explanation:
<em>Dew</em> is a manifestation of water condensation.
The air that surrounds us contains water vapor (humidity) from the evaporatoin of the water in the rivers, lakes, and the water with which you water the plants of your garden.
During the night, and specially in the early morning, before dawn, the temperature of the air descends, and part of the vapor in the air condensates in tiny droplets that accumulate over the surface of the plant's leaves, and other solid surfaces like the winshields and hoods of the cars.
Then, the phase transition that occurs is from gas (vapor) to liquid, which is called condensation and represented with the arrow labeled 4 on the diagram.